If the boat anodes are corroded, replace them. Installing fresh anodes will preserve and extend the life of your boat and underwater gear – shafts, struts, rudders, propellers, trim tab, engine, sterndrive – really just about anything that comes in contact with water.

It’s important when replacing anodes to choose the right type of marine anode for your application. Buying the wrong alloy for the water your boat goes in will make the anode useless.

For saltwater, use zinc or aluminum anodes.

For brackish water, use aluminum anodes.

For freshwater, use magnesium anodes.

Why Use Aluminum Anodes vs. Zinc?

Because aluminum anodes:

• Perform at least 5% better than traditional zinc anodes in salt water.

• Protect 50% longer than zinc anodes.

• Contain 0% cadmium, a toxic material found in zinc anodes which make them hazardous to the environment.

• Weigh 50% less than zinc anodes.

• Meet military specification MIL-A24779(SH).

• Represent the only boat anode proven to be effective in both salt and brackish water.

• Best of all, they result in considerable cost savings when compared to their zinc counterpart.

Anode Corrosion Factors

If a boat travels from one type of water environment to another, it’s crucial to check the anodes after every outing. For example, corrosion increases in saltier water. Corrosion increases with temperature. Pollution can also increase corrosion as in freshwater lakes contaminated by acid rain.

So moving from cold ocean water to warmer brackish water could deteriorate anodes at a much faster rate.

The relative size of a boat anode is small but can cause a world of damage should they become corroded.

The American Boat and Yacht Council (ABYC) set the standards for the industry. If you’re new to boat ownership, you may want to contact a mechanic with ABYC “Marine Electrical” or “Marine Corrosion” certification to help you determine the best anode material to use on your boat.

If you want to decide for yourself, here’s a good resource.

Or give our technical experts a call. They’ll be happy to guide you.